HALO-TO-HALO SIMILARITY AND SCATTER IN THE VELOCITY DISTRIBUTION OF DARK MATTER

Journal Article · Sun Feb 10 00:00:00 EST 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/764/1/35· OSTI ID:22167832

Mao, Yao-Yuan; Strigari, Louis E.; Wechsler, Risa H.; Hahn, Oliver ^[1]; Wu, Hao-Yi ^[2]

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1. Kavli Institute for Particle Astrophysics and Cosmology and Physics Department, Stanford University, Stanford, CA 94305, USAAND (United States)
2. Currently at Physics Department, The University of Michigan, Ann Arbor, MI 48109, USA. (United States)

We examine the velocity distribution function (VDF) in dark matter halos from Milky Way to cluster mass scales. We identify an empirical model for the VDF with a wider peak and a steeper tail than a Maxwell-Boltzmann distribution, and discuss physical explanations. We quantify sources of scatter in the VDF of cosmological halos and their implication for direct detection of dark matter. Given modern simulations and observations, we find that the most significant uncertainty in the VDF of the Milky Way arises from the unknown radial position of the solar system relative to the dark matter halo scale radius.

• OSTI ID: 22167832
• Journal Information: Astrophysical Journal, Vol. 764, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BOLTZMANN STATISTICS
DETECTION
DISTRIBUTION
DISTRIBUTION FUNCTIONS
MASS
MILKY WAY
NONLUMINOUS MATTER
SIMULATION
SOLAR SYSTEM
VELOCITY